Container closure construction



3 Sheets-Sheet 1 Filed Oct. 23, 1965 lA/l/EA/TOE VV/LL/AM J EC/(LES BY Eon/A20 0 OBQ/AM July 11, 1967 w. .1. ECKLES CONTAINER CLOSURE CONSTRUCTION Sheets-Sheet 2 Filed Oct. 23, 1965 2 m w w WILL/AM J. ECKLES 5r Eon A20 D. OBE/AN July 11, 1967 w. J. ECKLES 3,330,466

CONTAINER CLOSURE CONSTRUCTION Filed Oct. 23, 1965 3 Sheets-Sheet 5 I I I I 58 52 56 54 60 m/l/zA/me WILL/AM J. ECKL ES EDWARD D. OBR/AA/ ATTORNEY V United States Patent ()fifice 3,330,466 CONTAINER CLOSURE CONSTRUCTION William J. Eckles, 1117 S. Cambridge, Anaheim, Calif. 92805 Filed Oct. 23, 1965, Ser. No. 503,518

6 Claims. (Cl. 229-37) ABSTRACT OF THE DISCLOSURE At least two walls are provided on the closure end and three walls on the side immediately adjacent the closure end of this container. This is accomplished by double folding the side walls to obtain triple thickness on the side wall adjacent the end and notching out portions of this triple thickness on the side walls to form an overlapped side wall joint. The double thickness end closure is obtained by dimensioning the end closure flaps so that they form at least a double thickness of material throughout the end.

This invention is directed to container closure con structions, and particularly to superior, structually strong container end closure construction particularly useful for liquid containers made of relatively flexible material.

Container constructions of the general type of this invention are well known in the art. Such container constructions generally are embodied in milk containers, and such containers are sometimes used for other potable liquids. Such containers are made of fibrous material, a good grade of cardboard, which is suitably coated with a Waterproofing and sealant agent. The present day containers are disadvantageous because upon mishandling, the juncture between the bottom and side of such containers has a tendency to become damaged to such a point that the liquid leaks from the container. Such leakage renders the container unsalable, often renders the adjacent containers unsalable and permits the potable liquid to collect in the storage zone, requiring its cleaning.

Accordingly, it is an object of this invention to provide an end closure for containers made of flexible material of such nature that it can be made of one piece, is leakproof and is inexpensive and simple to manufacture.

It is another object of this invention to provide a strong bottom end closure which resists damage and thus resists leakage.

It is still another object of this invention to provide a container for liquids, which containers are capable of being manufactured in larger sizes due to the fact that the container has a strong, relatively leakproof bottom to thus facilitate stacking of containers, especially when they are provided with flat tops.

It is a further object of this invention to provide liquid containers made of flexible material which, due to the strong, relatively leakproof end closure construction can be made in larger sizes and in more convenient sizes to thus conserve shipping and storage space.

It is a further object of this invention to provide an end closure for a container made out of fibrous material having a thermoplastic coating and particularly a bottom construction which has a plurality of layers around the bottom corners and across the bottom so as to inhibit leakage and to create this bottom by thermoplastic sealing of thermoplastic coating without incipient leakage channels therein.

Other objects and advantages of this invention will become apparent from a study of the following portion of this specification, the claims and the attached drawings in which:

FIG. 1 is an isometric view of a flat top container having 3,330,466 Patented July 11, 1967 the bottom construction of the preferred embodiment of this invention;

FIG. 2 is a further isometric view thereof, taken from the bottom;

FIG. 3 is an enlarged section taken along the line 33 of FIG. 2;

FIG. 4 is a plan view of the blank used in creating the bottom construction of the preferred embodiment of this invention;

FIG. 5 is a partial plan view thereof, showing the first folds therein;

FIG. 6 is a section taken along the line 6-6 of FIG. 5;

FIG. 7 is an isometric view of the bottom of the container of the preferred embodiment showing the container rectangularly formed;

FIG. 8 is a view similar to FIG. 7 showing one bottom flap folded;

FIG. 9 is a view similar to FIG. 8 showing the folding thereof;

FIG. 10 is a similar view showing the completion of the closure;

FIG. 11 is a section generally taken along the line 1111 of FIG. 10;

FIG. 12 is an exploded view of the preferred embodiment showing a portion of the bottom and the side having a sealed overlap;

FIG. 13 is similar to FIG. 12, showing the further step in the formation of the side overlap at the bottom corner;

'FIG. 14 is an isometric view of another embodiment of the bottom closure of this invention; and

FIG. 15 is an enlarged section taken generally along the line 1515 of FIG. 14.

As an aid to understanding this invention it can be stated in essentially summary form that it is directed to an end closure construction for vessels or containers made out of flexible, coated fibrous material. In general this material is high quality cardboard having a thermoplastic coating. The invention comprises the first forming, by means of a double fold, of a rib which will finally occupy a position at the side wall adjacent the lower corner thereof. The second step comprises the formation of the rectangular cross section of the container. The third step comprises closing of the bottom flaps. By the particular design of the ribs and flaps, three layers of this cardboard material are presented at the side wallsthat are adjacent the bottom edge thereof and throughout the bottom. This construction resists damage, and thus it resists leakage. Furthermore, the various ribs and flaps are arranged so that they may be formed out of one piece of material for the convenience in forming the bottom construction. Sealing is accomplished thermoplastically, preferably through the agency of the thermoplastic coating' on the cardboard. Thus, this superior bottom construction is created.

This invention will be understood in greater detail by reference to the following portion of the specification wherein the drawings are described in detail. Referring now to the drawings, the preferred embodiment of the container of this invention is generally indicated at 10. The container 10 has its sides and bottom made out of a blank 12 of a single sheet of flexible material. The material of blank 12 is generally in the category of cardboard, being made of flexible, fibrous material suitably compacted and cal-endered for this service. Furthermore, for the containment of liquids the blank 12 is preferably created with a suitable waterproofing or other 'sealing material. Such materials are well known, and are normally' thermoplastic. Paraflin, or synthetic polymer composition materials are often used in this service.

Container 10 has a top 14. Top 14 is preferably of .the flat top construction so as to aid in stacking of the 3 containers. However, it may be made of the usual gabled construction, if desired. Furthermore, the container 10 has a lap side 16 and flat sides 18, 20 and 22. The blank 12 is closed to form the bottom construction of this invention, including the portions of the sides adjacent to the bottom. This bottom construction is generally indicated at 24.

Referring now more particularly to FIGS. 4 and 5, the blank used in forming the sides and bottom of the container 10 is shown in considerable detail. In particular, the fiat sides 18, 20 and 22 are shown as being separated by fold lines 26 and 28. Fold lines 26 and 28, as well as the other fold lines hereinafter described may be conventionally formed as by scoring so as to aid in folding along the proper line with a minimum of buckling. Furthermore, side panels 30* and 32 are respectively separated from sides 18 and 20 by fold lines 34 and 36. Side panels 30 and 32 overlap at seal zone 38 to form lap side 16. In FIGS. 4 and 5, dotted lines are used to indicate folds toward the viewer while dot-dash lines are used to indicate folds away from the viewer. Furthermore, FIGS. 4 and show a view of the side of the blank 12 which will be the exterior of the container 10.

Fold lines 40 and 42 are formed transversely across blank 12. Notches 44 and 46 are rectangular in form. In side panel 30 notch 44 is formed below fold line 42. In side panel 32 notch 46 is formed above fold line 40. Furthermore, the vertical height of the notches, as seen in FIG. 4, is substantially equal to twice the distance between the fold lines 40 and 42. The transverse total depth of both of notches 44 and 46 is equal to the overlap of lap side 16. Preferably, the transverse depth of the notches are equal to each other. As is seen in FIGS. 5 and 6, the first operation in forming the container is folding along lines 40 and 42 to form folds 40 and 42. These folds are made and scaling is accomplished to define rib 48.

After the formation of rib 48, folds are performed along fold lines 26, 28, 34 and 36 so as to form the rectangular body of the container 10. Formation of such a body is normally accomplished by automatic machinery, and the body is normally formed upon a mandrel. Rib 48 may be formed on the mandrel, or may be formed by a previous operation. At the time of formation, rib 48 is secured in place by heating and cooling in conjunction with the thermoplastic coating upon the material of blank 12. After folding along the fold lines the fold lines 26, 28, 34 and 36 define the corners of the body of the carton.

Referring again to the blank shown in FIGS. 4 and 5, a fold line 50 is arranged transversely of the blank above fold line 42. Fold line 50 becomes the fold at the bottom corner of the finished carton. Thus, the panels and the tabs above fold lines 50 in these figures form the bottom 24 of the finished carton. Side panels 30 and 32 extend upwardly beyond fold line 50 to form bottom panels 52 and 54. These are provided with the same dimensional overlap as side panels 30 and 32. The height of the panels above fold line 50 is substantially equal to the width of sides 18 and 20. Similarly, the side 22 extends upward beyond fold line 50 to form bottom panel 56. Bottom panels 52, 54 and 56 are each full length panels, each of which is capable of reaching across the bottom in the direction of sides 18 and 20. Short bottom panels 58 and 60 are formed in line with sides 18 and 20. These short bottom panels extend above fold line 50 at a predetermined dimension. This dimension is such that when the height of each of these short bottom panels 58 and 60 is added to the width of bottom panels 52 and 54 the total is substantially equal to twice the width of side 22. The resultant dimensional relationship is shown in FIG. 3.

Referring to FIGS. 11, 12 and 13, the formation of the lap side 16 in conjunction with rib 48 and a single bottom panel lapped from bottom panels 52 and 54 can be seen. As the joint is lapped on the sides 30 and 32,

4 the side 30 is laid exteriorly of side 32. As is seen in FIG. 5, notches 44 and 46 are closed by the fold of rib 48. These are shown in the partially folded configuration of FIG. 12. However, the lap is not accomplished until the fold is completed as is shown in FIG. 13. As the joint is accomplished with the overlap of side panel 30 exteriorly of side panel 32, the lap of bottom panel 52 on top of, as seen in FIG. 13, bottom panel 54, butt joint 62 is formed. Due to the depth of notches 44 and 46, butt joint 62 is formed substantially at the center of the overlap. Thus, the edges of both side panel 30 and side panel 32 extend transversely beyond the butt joint 62 so that at any point in the cross section there are at least two uninterrupted layers of material. Furthermore, to prevent an incipient leakage path at butt joint 62, an additional amount of pressure is applied at that point, during the forming of the body around the mondrel so as to especially compress that area. Furthermore, if desired, an additional amount of thermoplastic material can be supplied at that point to fill the butt joint, or the amount of pressure applied as well as the amount of thermoplastic layer on the blank material can be sufficient to fully seal butt joint 62.

At this stage of construction, the container 10 is in the condition shown in FIG. 7. As the next step, bottom panels 52 and 54, which are now secured together to effectively form a single bottom panel are folded inwardly to the position shown in FIG. 8. During the folding, short bottom panels 58 and 60, respectively, fold along fold lines 64 and 66 to respectively form folds 64 and 66. These folds define a miter corner in the manner shown in FIG.-8.

Referring now to FIG. 9, the next step in the closing of the bottom 24 of container 10 is shown. Fold lines 68 and 70 in short bottom panels 58 and 60 are folded inward at the same time that short bottom panels 58 and 60 are folded inward along fold line 50. At the same time outside bottom panel 56 is folded inward so that all folds are made at the same time. An intermediate position is shown in FIG. 9. When the fold is completed, the bottom 24 is closed as is shown in FIG. 10.

As has been previously stated, these bottom folds are made over a mandrel and external folding members and pressers are provided to bring the various panels into place. Sufficient force is exerted, together with sufficient temperatures along the adjoining faces of the panels to cause adhesion. In addition to adhesion, sufficient force is applied to seal over the whole area. In certain areas additional force may be required to assure a good seal along incipient leakage paths. These incipient leakage paths exist along the lap of bottom panels 52 and 54, at the edges 64 and 66 formed at the fold lines 64 and 66, as well as folds 68 and 70 along fold lines 68 and 70. However, rib 48 which extends around the side just above the bottom has three thicknesses of material throughout and the bottom has three thicknesses of material virtually throughout the whole bottom area. Thus, any incipient leakage paths are relatively long and tortuous so that sealing is readily accomplished. As previously stated, the areas in contact may be secured by the thermoplastic coating on the original blank, or may be secured to additional sealing and adhesive material. The areas in sealing contact are shown as stippled in the drawings.

Referring now to FIGS. 14 and 15, another embodiment of the container of this application is generally indicated at 80. The container 80 is formed of the identical blank 12 as the container 10. The container 80 is made out of blank 12 when the side of the blank 12 seen in FIGS. 4 and 5 is caused to be the interior of the container. Thus, rib 48 becomes rib 82 on the interior of the container. The similar parts of the blank, when folded into a container 80, are indicated with the same numerals as previously described, but carrying primes. It can be seen that this container is formed in similar manner and suitable forces are applied by the folding machinery to complete a firm, damage resistant lower corner and bottom. Again, the side Walls adjacent the lower corner are three thickness thick and the bottom is three thicknesses thick over substantial part of the area thereof.

While the closure described herein is particularly described with respect to the bottom of the containers and 80, it is clear that it is useful as a closure for either end of the container. It should be carefully noted that while the drawings show containers having a square horizontal section, the end closure construction of this invention provides a strong enough end to permit rectangular sections. Thus, low rectangular containers are permissible. For example, a two quart milk container corresponding in size to two, side-by-side quart containers can be made, and still have a strong, leak resistant end closure. Thus, easily storable sizes are permissible.

This invention having been described in its preferred embodiment and an alternative embodiment shown, it is clear that it is susceptible to numerous modifications and additional embodiments within the scope of this invention and without the exercise of the inventive faculty. Accordingly, the scope of this invention is defined by the scope of the following claims.

I claim:

1. A container closure construction, said container closure construction comprising:

a container body and a container closure end, said container body and said container closure end being formed of a single piece of flexible material, a first fold defining the corner of said container at the juncture between said container body and said container end, end closure panels on one side of said first fold, second and third folds on the body side of said first fold, said second and third folds forming a rib adjacent said first fold and adjacent the corner of said body at said first end;

first, second, third and fourth contiguous end panels, said first, second, third and fourth contiguous end panels being folded to form said end so that said end has two layers of material throughout its extent on the side of said first fold away from said body, the improvement comprising:

notches in said rib, said first panel being formed by overlapping said material, and said rib being formed both by overlapping and by notching so that three layers of material are maintained in said rib when the material is overlapped.

2. The container closure construction of claim 1 wherein said first end panel is joined with said second and fourth end panels by mitered fold corners and said third end panel is joined to said second and fourth end panels by mitered fold corners.

3. The container closure construction of claim 2 wherein said third panel is positioned on the exterior of said end, said second and fourth panels are positioned interiorly of said third panel and said first panel is positioned interiorly of said container.

4. A blank for the forming of a container body and a container end closure, said blank being made of foldable material, a first fold line on said blank, said first fold line defining the juncture between the body and the end closure, said blank having first and second edges, said first fold line extending from said first edge to said second edge, second and third fold lines adjacent said first fold line on the body side of said first fold line, said second and third fold lines extending from said first edge to said second edge of said blank, a first notch in said first edge of said blank and a second notch in said second edge of said blank, said first and second notches being positioned on the body side of said first fold line and adjoining said second and third fold lines; first, second, third, fourth and fifth bottom panels on said blank, said bottom panels being contiguous and being positioned on the end closure side of said first fold line, said first, third and fifth end panels extending a first distance away from said first fold line and said second and fourth end panels eXtending a second, shorter distance away from said first fold line, the total width of said first and fifth panels plus the second distance of said second and fourth panels being substantially equal to twice the width of said third panel so that said end panel, when folded, forms three thicknesses of material substantially over the entire end closure when folded.

5. The blank of claim 4 wherein said blank is provided with fold lines extending substantially parallel to said edges across the body portion of said blank and across the end closure of said blank and corresponding to the edges of said end panels of said blank.

6. The blank of claim 5 wherein said second and fourth end panels are provided with diagonal fold lines extending from the juncture of said fold lines substantially parallel to the said edges and said first fold line whereby said end panels can be folded together with mitered corner joints.

References Cited UNITED STATES PATENTS 1,158,130 10/1915 Hawkins 229-37 2,412,031 12/ 1946 Bergstein 229-37 2,474,523 6/ 1949 Guyer 229-37 2,596,225 5/1952 Eaton 229-37 2,990,996 7/1961 Powlenko 229-37 3,144,192 8/1964 Seline 229-37 JOSEPH R. LECLAIR, Primary Examiner. R. PESHOCK, Assistant Examiner. 

1. A CONTAINER CLOSURE CONSTRUCTION, SAID CONTAINER CLOSURE CONSTRUCTION COMPRISING: A CONTAINER BODY AND A CONTAINER CLOSURE END, SAID CONTAINER BODY AND SAID CONTAINER CLOSURE END BEING FORMED OF A SINGLE PIECE OF FLEXIBLE MATERIAL, A FIRST FOLD DEFINING THE CORNER OF SAID CONTAINER AT THE JUNCTURE BETWEEN SAID CONTAINER BODY AND SAID CONTAINER END, END CLOSURE PANELS ON ONE SIDE OF SAID FIRST FOLD, SECOND AND THIRD FOLDS ON THE BODY SIDE OF SAID FIRST FOLD, SAID SECOND AND THIRD FOLDS FORMING A RIB ADJACENT SAID FIRST FOLD AND ADJACENT THE CORNER OF SAID BODY AT SAID FIRST END; FIRST, SECOND, THIRD AND FOURTH CONTIGUOUS END PANELS, SAID FIRST, SECOND, THIRD AND FOURTH CONTIGUOUS END PANELS BEING FOLDED TO FORM SAID END SO THAT SAID END HAS TWO LAYERS OF MATERIAL THROUGHOUT ITS EXTENT ON THE SIDE OF SAID FIRST FOLD AWAY FROM SAID BODY, THE IMPROVEMENT COMPRISING: NOTCHES IN SAID RIB, SAID FIRST PANEL BEING FORMED BY OVERLAPPING SAID MATERIAL, AND SAID RIB BEING FORMED BOTH BY OVERLAPPING AND BY NOTCHING SO THAT THREE LAYERS OF MATERIAL ARE MAINTAINED IN SAID RIB WHEN THE MATERIAL IS OVERLAPPED. 